hubieran culpado
-they/you had blamed
Antecopréterito de subjuntivo para el sujeto ellos/ellas/ustedes del verbo culpar.

culpar

Los sobrevivientes hubieran culpado a los líderes por no haber tomado medidas para impedir esta guerra de exterminio.
Those who survived would have blamed the leaders for not having taken the measures that would have avoided this war of extermination.
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